1. Field of the Invention
This invention relates to a pipe splitting device and more specifically to a device which splits a buried pipe along a longitudinal path of the pipe to be split while simultaneously positioning a replacement pipe therefor.
2. Description of Related Art
In an effort to replace buried pipe which has lost its use because of age or size, it becomes necessary to unearth the old pipe and replace it install new piping within the old pipe or break-up the old pipe and replace it with a new pipe. Installing new piping within the old pipe means that the bore of the replacement pipe is less than the old pipe through which the new piping is threaded. Recently, a method and apparatus for replacing buried pipe with the same or larger dimension and the existing pipe has been described in U.S. Pat. No. 4,507,019. The apparatus employes a mandrel with a plurality of hard metal boring buttons such as tungsten carbide to score the internal surface of the existing pipe. The buttons are positioned on a pipe expansion section which causes the existing pipe to break apart when forced through the existing pipe. A replacement pipe is simultaneously positioned during the passage of the mandrel through the existing pipe. The mandrel is pushed through the existing pipe with a jacking machine having a thrust force of about 160,000 to 300,000 lbs. A winch may add an additional pulling force of about 5,000 lbs.
A self-propelled apparatus is taught in U.S. Pat. No. 4,674,914 for replacing gas mains. This device is hydraulically operated, slides within the existing pipe, grips the internal surface of the existing pipe and utilizes a vibratory means to breakup the existing pipe. The device tows a replacement pipe.
The prior art fails to teach a pipe splitting device which is pulled through an existing pipe with a single cutter wheel for splitting the existing pipe along a longitudinal path of the existing pipe while simultaneously replacing the existing pipe with a new replacement pipe.
An object of the invention is to provide a pipe splitting device with an elongate frame which may be used in splitting different diameter pipes along a longitudinal path of the pipe to be split.
Another object of the invention is to provide a pipe splitting device with an elongate frame which accepts a different sized cutting wheel and different sized rollers and different sized side wheels to enable the cutting of different size bores by interchanging a different sized cutting wheel, rollers and side rollers.
Another object of the invention is to provide a pipe splitting device with an elongate frame which does not provide a wearing surface thereon thereby lessening the frequency of replacement of the elongate frame.
Another object of the invention is to provide a pipe splitting device which is maneuverable around bends in the existing pipe.
Another object of the invention is to provide a pipe splitting device which enables the replacement pipe to be larger than the existing pipe it replaces.
Another object of the invention is to provide a pipe splitting device which forms a single longitudinal cut along a longitudinal path of the pipe to be split.
Another object of the invention is to provide a pipe splitting device which may be moved longitudinally within a length of pipe to effect slitting of the pipe from within the bore of the pipe.
Another object of the invention is to provide a pipe splitting device which may be orientated within the pipe to be split such that the lower portion of the pipe to be split is cut by the cutting wheel thereby enabling an expander to spread the pipe cut to provide a cap over the newly positioned replacement pipe simultaneously positioned during the splitting process.
Another object of the invention is to provide a pipe splitting device which requires less pipe splitting force than conventional internal pipe splitting devices.
The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed to be merely illustrative of some of the more pertinent features and applications of the invention. Many other beneficial results can be obtained by applying the disclosed invention is a different manner or modifying the invention within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description describing the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.